The important thing in a freedom is of course size (we don't have much room to spare). I have two, an 800w oil filled radiator and a small cheap fan heater for instant warmth. The radiator is a six fin model and is approx 30cm x 40 cm (12 x 16 in old money) and gives out a reasonable amount of heat whilst still allowing you to boil your low wattage kettle! There are dozens on e-bay/ amazon at around £20. Small fan heater from B&M, £9.99, silent, thermostat, works well for the price.
We use a two speed fan heater which also blows cold and find it plenty good enough for our needs, we did try one of those oil filed things but found it more of a nuisance them it was worth, if we are using too much wattage we just turn it off for a bit and when turned back on it soon warms the vast area up.